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In the Rust By Example book show us a way to handle errors in the map method of Iterator:

 let strings = vec!["93", "tofu", "18"]; let numbers: Result<Vec<_>, _> = strings.into_iter().map(|s| s.parse::<i32>()).collect(); println!("Results: {:?}", numbers);

Is it a similar way to deal with errors in Option like the following?

 let a: Option<&str> = Some("tofu"); let b: Result<Option<i32>, _> = a.map(|a| a.parse::<i32>()); println!("Results: {:?}", b);
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There is a handy method called .transpose() that can convert an Option<Result<T, E>> into a Result<Option<T>, E> (or the reverse):

let a: Option<&str> = Some("tofu"); let b: Result<Option<i32>, _> = a.map(|a| a.parse::<i32>()).transpose(); println!("Results: {:?}", b);
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